It is known to form an electrical connection between two complementary surfaces with a contact sheet or strip as described in U.S. Pat. No. 3,453,587 issued on July 1, 1969 which is a strip of resilient metal formed with a plurality of parallel slits that subdivide its central region into a plurality of parallel tongues or contact lamellae extending between coplanar side portions. These tongues are twisted to lie at an angle to the plane of the side portions. Such a connector is compressed between the two complementary surfaces, resiliently deforming the lamellae so as to make a very good electrical connection.
One of the factors which influences the electrical resistance offered by such a connector is the force with which the lamellae bear on the surfaces: the greater the force the less the resistance. Another factor is the number of lamellae since each lamella only bears with one edge on one surface and with its other edge on the other surface. A compromise must be made between the two factors since, if the number of tongues or lamellae is increased by decreasing the width of these lamellae, the force which the tongues exert on the surfaces is also decreased as their capacity for elastic deformation is decreased, and vice versa.
This disadvantage was overcome in the above-mentioned patent application Ser. No. 392,517 in a connector wherein the side portions are longitudinally corrugatedly contracted. By this it is meant that these portions have a developed and extended length which is substantially greater than the length of the contracted strips. This effect is achieved according to a feature of this earlier invention by corrugating or wrinkling the side portions.
Hitherto the principal method of connecting a conductor, such as a cable, to a battery terminal has been by means of a so-called clamp or screw connector. Thus the terminal is provided with a connector pin over which a screw-tightenable sleeve is secured. Such an arrangement does form a good electrical connection between the two elements so long as the members fit each other exactly, but has the considerable disadvantage that a screw must be loosened in order to disconnect the two. In addition a screw must be tightened to connect the two securely together so that changing batteries is a lengthy and difficulty operation.